Infestation

Infestation is a vanilla-compatible single-level PWAD for Doom, designed by Nicholas Bell and released in July 1994.

A modified version of this level appears as E1M3 in the 1995 WAD compilation, Heroes.

Secrets

 * 1) Immediately north of the start is a secret door leading to a shotgun (three on multiplayer), a box of shotgun shells (two on multiplayer), and an armor (three on multiplayer). (sector 224)
 * 2) The building in the centre of the courtyard near the start has a secret door on the west wall at the top of the north-east staircase (marked with a misaligned texture) leading to a chainsaw, two medikits, and an imp (hard skill only). (sector 50)
 * 3) The central door on the south corridor in the same building (see #2) leads to a room with a switch which opens up a door to a passage leading to a rocket launcher. At the end of this passage is a secret door on the north wall (marked with a different texture) leading to a berserk. (sector 176)
 * 4) From the north-west area overlooking the room with the triangular nukage pit, go through the door to the west, head round, then take a door to the east. Immediately ahead is a secret door (marked with a different texture) leading to a shotgun guy (two on hard skill), an imp (not on easy skill), and a secret door (marked with a different texture) leading to a soul sphere. (sector 228)
 * 5) From #4, head back through the door and down the stairs to the north. Go through the door to the west leading to a room with two large rotating columns. Between them is a secret door on the west wall (marked with metal supports) leading to a room with 1-3 imps and a switch. This switch reveals a room with a switch (and an imp on hard skill) which opens up a room north of the large rotating columns containing a plasma rifle, a box of rockets, a box of shotgun shells, a megaarmor, three medikits, two imps (one on easy skill), and (on hard skill) a cacodemon. (sector 232)
 * 6) Directly west of the red key is a demon face wall which is a secret door leading to a soul sphere. The alcove to the north of it has a secret door on its west wall (marked with faces) leading to two imps (one on easy skill), three medikits, a megaarmor, and six energy cell packs. (sector 181)
 * 7) East of the red key is a red door leading to a room with two imps (one on easy skill), a radiation shielding suit and a partial invisibility. The back wall of this room is a secret door which on opening also opens a door ahead leading to a room with 0-3 imps, a BFG9000, a megaarmor, four energy cell packs (six on hard skill), and a yellow key. (sector 237)
 * 8) Directly opposite the yellow door in the west of the level (in the long lava trench) is a secret door leading to a radiation shielding suit. (sector 241)
 * 9) West of the blue key is a secret door leading to two medikits, a soul sphere, a megaarmor, an energy cell pack, and four boxes of rockets. (sector 252)
 * 10) From the room with the nukage triangle, take the south-west door and go through the crushers to reach a lift. Just before the lift is a blue door on the south wall, leading to a room with some monsters and five health bonuses. Approaching the health bonuses opens a nearby door, revealing 0-5 imps, two medikits, an armor, and some ammo. (sector 209)
 * 11) Entering #9 opens up two passages surrounding the courtyard at the start. The southern one leads to a computer area map - approaching it opens up a secret door leading to three imps (2 on easy skill), a shotgun guy (hard skill only), a box of bullets, a box of shotgun shells, and an energy cell pack. (sector 261)
 * 12) As the northern passage (see #10) is entered, a secret door opens up at the south-east corner of the passage leading to two shotgun guys (one on easy skill), a zombieman (two on hard skill), two medikits, two boxes of bullets, an energy cell pack, and an armor. (sector 207)

Secret exit: After entering #9, return to the start where the door immediately west of the start will have opened, revealing the secret exit switch.

Current records
The records for the map at the Doom Speed Demo Archive are:

The (absence of) data was last verified in its entirety on September 7, 2023.

Things
This level contains the following numbers of things per skill level: